Change on representation in problem solving strategies

Researches that have analysed the change in problem solving ability from lower to higher levels, focus either on quantitative increase in the information processing demands (Case, 1984; Klahr & Robinson , 1981), or on qualitative change in the organisation of representations (Bidell & Fischer, 1994; Piaget, 1974). This study is a repetition of Fireman research (1996). Our purpose is to determine the utility of these two approaches to problem solving through a microgenetic analysis of children’s attempts to solve the Tower of Hanoi task. The trial we use is a computerised version of the problem that provides the utilisation of the keyboard interface in a simply way. As Siegler e Crowley (1991) suggest, the microgenetic approach can be particularly useful in understanding transitions in cognitive development. 58 children 6-8 years old were presented with the three disks version of the Tower of Hanoi task. Each subject was tested separately. A time limit of 3 minutes was given for the task solution. The quality of the performance was analysed by observing the correctness of the first move, the number and the location of optimal and illegal moves, the problem depth, and several temporal variables (latency time, move execution time, initial planning time). The results indicate that both qualitative and quantitative changes in the representation of the problem space are an important aspect of successful performance. Moreover, the strict time limit employed in this study favours most efficient children.